Aircraft structure



Nov. 14, '1944. R w MILLE'R 2,362,919

AIRCRAFT STRUCTURE 2 Sheets-Sheet l lNvNToR ATTORNEY NV11.1944 R.w. MILLER l 2,362,919 AIRCRAFT STRUCTURE I Filed Nov. 21, 1941 2 sheets-sheet 2 V ATTORNEY y v y Patented Nov. 14, 1944 STRUCTURE Robert Wendell Miller, Farmingdale, N. Y., assignor to Republic Aviation Corporation, a corporation of Delaware e Application November 21,1941, Serial No. 420,008 fs claims. (o1. 244-102) The invention relates to improvements in fully retractable landing gear-for aircraft and is more specifically concerned with the' wheel fairing used in connection with such landing gear to n cover the wheels in their retracted position and form then a substantial continuation'of the wing under-surface The general object of these improvements is to reduce to a minimum the number of auxiliary parts, fairing, links, levers, braces, etc. projecting below the lower surface of the wingin the extended position of the landing gear, as these parts are then exposed and will beI sprinkled with mud when the aircraft' is taxied across a wet airfield and in order t minimize the drag.

More specifically, the object ofthe invention is to eliminate the section offairing usually found adjacent the lower part of each wheel, from the landing gear itself, and to mount this section directly on the wing.

tion between these two aps and the cross heads of the landing gear retracting mechanism, which will be entirely encl'osed within the wing even in the extended position of the landing gear, and 'which will be such that these flaps will be automatically swung clear of the wheel as this latter moves from or enters the wing and will be returned back into their closed position immediately after each extension or retraction of the landing gear.

A further feature consists in adapting each inner hinged flap for carrying a ksection of the supercharger duct, thereby allowing thisvsec'tion to be moved out of the way of the wheel, both when the landing gear is retracted and folded I inward within the' wing or is swung outward and extended-in its active position.

Other features of the invention will become apparent from the reading of the'following description, made in reference to the accompanying drawings, which show, as an example,v one embodiment of the invention.` `It is to beiunder- VFigure 2.

and carrying a section'l of a supercharger duct stood, however, that the invention is limited in o In these drawings:

Figure l is a fragmentary bottom view of an aircraft, showing the central portion of the wing enclosing this embodiment of the landing gear according to the present invention and the fair- -ing parts in their closed position;

Figure 2 is a fragmentary front elevation of this aircraft, showing the landing gear lin its active position and having parts broken away to show the details of thev mechanical connection between the crosshead of the landinggear retracting mechanism and the hinged flaps of the fairing;

Figure 3 is a view similar to Figure 2 showing the landing gear Ain an intermediary position, andthe two hinged flaps in their open position;

Figure 4 is another view similar to Figure 2, showing the landing gear in its closed or retracted position; and

Figure 5 is a fragmentary side elevation corresponding to Figure 2 with the wing shown in transversal section along line 5-5 of this -In'these i'igures, II indicates the fuselage of the aircraft and I2l the wing. 'Ihe wheel fairing of the landing gear comprises a pair of inner flaps I3, each hinged at I4 to the wing structure I 6, a pair of outer flaps I'I, likewise hinged at I8 to the wing structure and a pair of middle portions i9, permanently and rigidly attached to the oleo shock absorbing struts 2i, carrying the wheels 20 for ground contact.

A mechanical connection between each strut 2I and the corresponding inner iiap I3 of the fairing is established by the intermediary of a link 23, pivoted to this flap at 22 and to a rst lever 25 at 24. y

Each of these levers 25 is pivoted at 26 to the wing structure and ispivotally linked to a second lever 28 through the intermediary of a link 21.

Each lever 28 comprises an arm 30, pivoted to a booster cylinder 3|, and a second arm 32, pivoted to a link 33, which in turn is pivoted to a bracket 34, vcarried on the crosshead 35 of the landing gear retracting mechanism.

A similar, though simpler, mechanical connection between each of the crossheads 35 and the corresponding outer. flap Il is established by means of a link 36, pivoted respectively to the flap at 31 and to the crosshead at 38.

The crossheads 35 move inboard as the landing gear is extended. 'I'his action presses the links 3,3 inboard and, through 'the levers 28, 25

, 'u lowers automatically the fairing flaps Iiv in the movement of the oleo-struts 2 i.

` retracted. comprisinga nap position shown in lligure 3 before each swing- 'ing outward and down oi' the wheels 20 so as to clear ythe passage of these wheels, while simul-l to their retracted position of Figure 4 atl the end of the take-ofi, the a'ps i3, I1 are successively by the reversed I re-opened and .closed again Each inner hinged ap i3 is provided around I each joining edge ofthe duct section II vwith suitable washer .(not shown) to insure proper tightness of the two joints lS-and the rest I8 of the supercharger ducts.

l Having now made certain the nature and purbetween this section poses of my invention," and at least one Vmode oi executing same in such manner as to enable any- 'one skilled in the-art to which it apertains to make and use same, as required bythe statuteaf that which I claim as'my property and odesire'to secure by- Letters Patent oi' the United States e of America is:

' 1; `In `an faircraitv landing-gear system including a landing-leg carrying a wheel: aleg-andwheel fairing group, comprising a middle fairingportion .rigidly attached to the'leg; an inwardly rotatable ilap pivotally mounted on the aircraftA l inboard of the landing-legimounting; and au outwardly rotatable nap pivotally mounted on the "aircraft outboardoi' said landing-leg mountthe'ty'pe includinga cantilever landing-leg and wheel retractable into a center-sectionof a thin wing: a lleg-a'ndwvheel viairing group. comprising .a middle faking-portion rigidly attached to the leg; -a 'a'p pivotally mounted directly on said center-section vand adapted to -be indirectly opened by thel movement of said legi and another iia'p freely rotatably mounted directly on another 2. In anfaircraft cantilever landing-gear. of-

maior component-of the aircraft and adapted Y' It; be indirectly rotated by the movement of said -3.1n an aircraft landing gear or the type m cluding a leg and wheel retractable into .a leg 'and wheel well: fishing-group for normally covering the 'maior area of said well `both when the leg is fully protracted and when it is iully pivotedf at the inf, board end. of said well and provided for maintaining it in closed the leg `either protracted or retracted: a ilap pivoted at. the outboard end ot said well and provided with means for maintaining it in closed position with the leg either protracted or retracted; and a common means for swinging both naps open to clear the path of the leg and wheel upon the beginning of both retraction and protraction thereof. t

4. In an aircraft landinggear of the type in.= cluding a leg-and-wheel retractable into a well: a {airing-group for completely closing the entire area of said well both when the leg is fully protracted and when the leg is fully retracted. comprising a {airing-portion pivotally mounted. nearthe inboard end of said well and normally maintained fin closed position; a fairing portion rigidly Imounted on said leg; a faking-portion Divotally'mounted near the outboard end oi said well and normally maintained closed; means con= nected .to said leg and said ilaps for opening both said ilaps when vsaid leg begins to move from either the fully retracted ,or the fully extended positions; and means for returningsaiwaps to their normal position when said leg returns to 4its fully retracted or fully protracted position.

' 5. In a fairing system fora power-retracted leg-and-wheel: a pivotallyv mounted fairing section; an auxiliary power-source; a lr system articulatedV at one end to the nap and terminating at the other end in a bell-cr; .a connection between one arm of the bell-crank and said auxiliary; and a connection between the other arm of the bell-crank and the leg.

6. In an aircraft landing gear fairing system: a fairing sectionfpivotedv on the aircraft; a rst link-member pivoted to said section; a irst lever, having two arms, pivoted to the aircraft outboard of said link; a pivotal connection between vthe iirst one of said arms and said rst linlr ;,a second link pivoted to the second one of said arms; a second lever pivotally mounted outboard of the second link and having three arms, `one of said 'arms being pivoted to the proximate end of said second link; a third linl:

'1. In an .iur-craftv having a landing leg and wheel retractable into a maior component and including' a conduit a movable ,sectionnormally lying in the path of movement of ,said leg and wheel: 'a'iiap pivotedto said major component to swing into and out of the path of movement ot the said leg and wheel, said -ilap carrying the movable section aforesaid.

8. In an aircraft' having a landing gear retractable into a major component, said aircraft including a conduit 1 having a movable section extending through the @retraction path of the gear, a flap pivoted to said major com- ;ient to ne 1n said path; said nap carrying the am d movable section of'said conduit that liu? said path.

'. RQBERT WENDELL MILLER. 

